程序本身有效，但我在循环中挣扎。我是一个使用循环的初学者，我一直在寻找适合我的程序类型的例子，但遗憾的是找不到任何例子。
我知道如果身体内有某些东西可以使条件“假”，那么循环就会停止。但对于这个程序，当它要求使用时，如果它想再次播放，将决定。但是，我的程序不会询问用户是否要继续。如果用户决定停止，那么该程序应该说“感谢您的发挥！”＃34;相反，它不断循环整个身体。
感谢您的帮助！
这是我的循环：
// Start loop
while (looping == true) {
// Ask if the # > 5
System.out.println("Is your number greater than 5? (True = 1, False = 0)");
// Read in the number
numberOne = input.nextDouble();
if (numberOne == 1) { // Is the # > 7?
System.out.println("Is your number greater than 7? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 1) { // Does the # = 8?
System.out.println("Is your number 8? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 0) { // If # != 8, then # = 9
System.out.println("Your number is 9!");
} else {
// If answer was 8, then yay
System.out.println("Yay! Got it!");
}
} else if (numberOne == 0) { // If # !> 7, then # = 6?
System.out.println("Is your number 6? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 0) { // If # != 6, then # = 7
System.out.println("Your number is 7!");
} else {
//If answer was 6, then yay
System.out.println("Yay! Got it!");
}
}
} else if (numberOne == 0) { // If the # !> 5, then # > 3?
System.out.println("Is your number greater than 3? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 1) { // If true, does your number = 4?
System.out.println("Is your number 4? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 0) { // If # != 4, then # = 5
System.out.println("Your number is 5!");
} else {
// If answer was 4, then yay
System.out.println("Yay! Got it!");
}
} else if (numberOne == 0) { // If false, # = 2?
System.out.println("Is your number 2? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 0) { // If # != 2, then # = 3
System.out.println("Your number is 3!");
} else {
// If answer is 2, then yay
System.out.println("Yay! Got it!");
}
// Ask user if they want to play again
System.out.println("Would you like to play again? (Yes = 1, No = 0)");
numberOne = input.nextDouble();
System.out.println("Thanks for playing!");
}
}
} // end loop
// Close input
input.close();
} // end method
} // end class
答案 0 :(得分：2)
因为您没有更改looping变量值。并移到else if()块之外的代码下方。
...
System.out.println("Would you like to play again? (Yes = 1, No = 0)");
looping = input.nextBoolean();
if (looping == false) {
System.out.println("Thanks for playing!");
}
...
您的代码将如下所示
// Start loop
while (looping == true) {
// Ask if the # > 5
System.out.println("Is your number greater than 5? (True = 1, False = 0)");
// Read in the number
numberOne = input.nextDouble();
if (numberOne == 1) { // Is the # > 7?
System.out.println("Is your number greater than 7? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 1) { // Does the # = 8?
System.out.println("Is your number 8? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 0) { // If # != 8, then # = 9
System.out.println("Your number is 9!");
} else {
// If answer was 8, then yay
System.out.println("Yay! Got it!");
}
} else if (numberOne == 0) { // If # !> 7, then # = 6?
System.out.println("Is your number 6? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 0) { // If # != 6, then # = 7
System.out.println("Your number is 7!");
} else {
//If answer was 6, then yay
System.out.println("Yay! Got it!");
}
}
} else if (numberOne == 0) { // If the # !> 5, then # > 3?
System.out.println("Is your number greater than 3? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 1) { // If true, does your number = 4?
System.out.println("Is your number 4? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 0) { // If # != 4, then # = 5
System.out.println("Your number is 5!");
} else {
// If answer was 4, then yay
System.out.println("Yay! Got it!");
}
} else if (numberOne == 0) { // If false, # = 2?
System.out.println("Is your number 2? (True = 1, False = 0)");
numberOne = input.nextDouble();
if (numberOne == 0) { // If # != 2, then # = 3
System.out.println("Your number is 3!");
} else {
// If answer is 2, then yay
System.out.println("Yay! Got it!");
}
}
}
// Ask user if they want to play again
System.out.println("Would you like to play again? (Yes = 1, No = 0)");
looping = input.nextBoolean();
if (looping == false) {
System.out.println("Thanks for playing!");
}
}
// Close input
input.close();
}
}
答案 1 :(得分：0)
// for(intialise ; testing Condition; increment/decrement)
for (int i = 0; i < 5; i++) {
}
// while(condition)
// first the condition get evaluated, if true the loop body is executed
int i = 0;
while (i < 5) {
// logic goes in here
i++;
}
// do{
// your code goes in here
// }while(condition);
// the loop gets executed once, then the condition is evaluated, if true
// loop is executed again
i = 0;
do {
} while (i < 5);
您可以在案例中使用while或do while循环。
looping = true;
while (looping) {
// your code
// Ask user if they want to play again
System.out.println("Would you like to play again? (Yes = 1, No = 0)");
numberOne = input.nextInt();
//You can use a simple if else statement also
if(numberOne == 1){
looping = true;
}
else{
lopping = false;
}
}
// if you wish to use a do while loop:
do {
// your code
numberOne = input.nextInt();
// ternary operator
looping = (numberOne == 1) ? true : false;
} while (looping);
Ternary Opeartor：
是一个非常有用的运算符，我们有时可以使用它来压缩if-else块在一行中
以最多两个数字为例。
if(a > b){
max = a;
}else{
max = b;
}
使用三元运算符可以简化并压缩成一行：
max = (a>b)?a:b;
一般语法是
(cond)?(value to return when cond true):(value to return if cond false);